Mischa, 27, who shot to stardom playing lead character Marissa Cooper, ruled out a possible return to show following last week's nostalgic 10-year anniversary.
She told Us Weekly: "Things have to feel right and it doesn't feel right."
Mischa's admission may come as a shock to fans, who are desperate to see the popular Newport gang reunite, but the actress explained that she didn't want to get "sucked back" into the limelight of the show.
The O.C. landed on TV screens in 2003, marking a decade since fans watched the fictional lives of a group of teenagers living in the Orange County, California.
The show also made stars of Benjamin McKenzie (Ryan Atwood), Adam Brody (Seth Cohen) and Rachel Bilson (Summer Roberts) but Mischa, whose character was killed off at the end of season three, said she no longer stays in contact with them.
One person who does want to relive the show's past, is show creator Josh Schwartz. Last week he told TV Guide that a reunion would only happen if all cast members were keen on it.
He said: "You know we wanted to do a reunion for the 10-year [anniversary], but in order to do that we wanted everybody to participate and to want to participate."
Considering Mischa's character was killed off, we're quite interested in how they would address that if a reunion ever did happen...
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